It has a long been the desire of the polymer industry to provide a wood or concrete substitute which is sufficiently inexpensive and ensures a long service life. Current structural composites utilized for solid wood or pallets are particle boards covered with thermoplastic or thermosetting resins. Examples area found in many patents. For example, the patent to Rettenmair (WO 03/008494) elaborates granular filling material comprising natural cellulose fibres in synthetic thermoplastic material which is used for producing moulded bodies, while that of Shalashov (RU 2186808) describes a pressure composition for wood board fabrication based on ground wood and vegetable particles and diphenylolpropane resin. A composition for synthetic wood based on a thermoplastic resin, shredded wood and a lubricant is patented by Yasushi (JP 2002347009) whereas a composition based on high strength, high modulus fibres in uncured adhesive used for reconstituted wood product is explained in the patent to Tingley (WO 99/55979). Lipman (WO 02/12645) explains the use of elongate synthetic wood mouldings formed of a settable wood paste comprising wood flour, a binder and a solvent that is flexible or stiff under conditions of processing, A significant disadvantage, of all these materials described above, however, is their high density, low stiffness and high manufacturing costs. Another disadvantages is that these materials can not be formed to thickness higher than 50 mm. Yet another disadvantage is that these material can not be used for repeated compressive or bending stress of more than 3 Mpa. Hence, there is a need for a lightweight but stiff composite structure that has longer life and can be used repeatedly for load bearing applications. One of the many ways to improve the strength and stiffness is the use of special or corrugated structures in certain paperboards and pallets, examples of which may be found in the patent to Gilbert, U.S. Pat. No. 3,629,046 (rectangular wood frame and core consisting of a slab of polystyrene sandwiched between two sheets of corrugated cardboard); Palmer, U.S. Pat. No. 4,265,067 (foamed plastic core panel comprising an inner core of corrugated plastic foam); Stayner U.S. Pat. No. 4,837,999 (a prefabricated building panel having a center core with an inner and outer skin coupled by pultrusion); Bainbridge U.S. Pat. No. 5,057,176 (automotive headline comprising of a laminate of double corrugated paperboard); Clasen, U.S. Pat. No. 5,076,176 (a lightweight pallet composed of layered and bonded corrugated cardboard material); Hofman et al, U.S. Pat. Nos. 5,364,178 (a metal case made up of an inner framework of corrugated metal panels encased in a metal wrapper), and Hutchison, 5,422,156 (a shipping pallet constructed of multiple lamination of corrugated sheet material made up of paperboards, fiberboards or plastic). However, one of the major disadvantages of many of these items is that all these cannot be used repeatedly under compressive or bending stress of more than 3 Mpa. Another key drawback is the inability of these items to be constructed of more than 50 mm thickness.
Till date, no one has combined the various structural features and material compositions disclosed in the present so as to address and overcome problems and shortcomings associated with all of the following: weight, strength, durability, malleability, modularity, insulating quality and load bearing under compression or bending modes.